Multiple birds (near always the same species) behaving as a group. Distinct from Too Many Birds in that the birds must be a grouping in some way (Eg, being clustered together or flying together), for instance a pet store featuring countless cages with a few birds each or a series of taxidermy animals would be not count as flock but could be too_many_birds.
Too Many Birds not Flock: post #6692857 post #6949868 post #114802
Flock and Too Many Birds: post #6709824 post #5779985 post #6626571 post #6237359
In cases where a character is surrounded by birds that appear to have been startled post #6244855 it is generally safe to tag flock.